Noticed my 1993 1600td LHD Westy was not as economical as before, looked at the back after a long journey to see diesel dripping from the bottom of the engine and silencer. Looked in engine bay while engine was running, revved it up and diesel squirts out of the flange bit in the centre of the pic below. I have pulled this a bit and it seems to be loose, lifting by about 3mm. Should this have a seal or just be tightened up? The greenish looking nut in the centre of the pic seems tight.

SINCE BROWSING THE FOR SALE ITEMS, I NOW KNOW THAT THE PART IN THE PIC IS THE TOP OF THE FUEL PUMP. MAY HELP WITH ANY ANSWERS!!
Replies appreciated.
Matt